Scalable cloud storage architecture

Abstract

a virtual storage module operable to run in a virtual machine monitor may include a wait-queue operable to store incoming block-level data requests from one or more virtual machines. In-memory metadata may store information associated with data stored in local persistent storage that is local to a host computer hosting the virtual machines. The data stored in local persistent storage replicates a subset of data in one or more virtual disks provided to the virtual machines. The virtual disks are mapped to remote storage accessible via a network connecting the virtual machines and the remote storage. A cache handling logic may be operable to handle the block-level data requests by obtaining the information in the in-memory metadata and making I / O re-quests to the local persistent storage or the remote storage or combination of the local persistent storage and the remote storage to service the block-level data requests.

Description

FIELD[0001]The present application generally relates to computer systems and computer storage, and more particularly to virtual storage and storage architecture.BACKGROUND[0002]Designing a storage system is a challenging task. For instance, in Cloud Computing, high degree of virtualization increases the demand for storage spaces and this requires the use of remote storage spaces. However, uncontrolled access to the remote storage from large number of virtual machines can easily saturate the networking infrastructure and affect the entire systems using the network.[0003]More particularly, for example, in an IaaS (Infrastructure-as-a-Service) cloud services, storage needs of VM (Virtual Machine) instances are met through virtual disks (i.e. virtual block devices). However, it is nontrivial to provide virtual disks to VMs in an efficient and scalable way for a couple of reasons. First, a VM host may be required to provide virtual disks for a large number of VMs. It is difficult to asce...

AI Technical Summary

Benefits of technology

[0004]A storage system and method for handling data for virtual machines, for instance, for scalable cloud storage architecture, may be provided. The system, in one aspect, may include a virtual storage module operable to run in a virtual machine monitor. The virtual storage module may include a wait-queue operable to store incoming block-level data requests from one or more virtual machines, and in-memory metadata for storing information associated with data stored in local persistent storage that is local to a host computer hosting the virtual machines. The data stored in local persistent storage may be replication of a subset of data in one or more virtual disks provided to the virtual machines, the virtual disks being mapped to remote storage accessible via a network connecting the virtual machines and the remote storage. A cache handling logic may be operable to handle the block-level data requests by obtaining the information in the in-memory metadata and making I/O requests to the local persistent storage or the remote storage or combination of the local persistent storage and the remote storage to service the block-level data requests.

[0005]A

Problems solved by technology

Designing a storage system is a challenging task.

However, uncontrolled access to the remote storage from large number of virtual machines can easily saturate the networking infrastructure and affect the entire systems using the network.

However, it is nontrivial to provide virtual disks to VMs in an efficient and scalable way for a couple of reasons.

It is difficult to ascertain the largest possible storage demands and physically provision them all in the host machine.

On the other hand, if the storage spaces for virtual disks are provided through remote storage servers, aggregate network traffic due to storage accesses from VMs can easily deplete the network bandwidth and cause congestion.

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